Optical depth is a key factor for the study of aerosol content calculation, the degree of atmospheric pollution and atmospheric radiative transfer. Transmission function, reflection function, single scattering albedo and other important physical parameters of atmospheric transmission are functions of the optical depth. The database of complex refractive index in typical days is established, and aerosol particle size distribution model is improved based on experimental data. Considering atmospheric visibility and other atmospheric parameters in Dalian, the aerosol optical depth is calculated based on the Mie scattering theory.

The numerical simulation method of thermal blooming adaptive optics (AO) phase compensation is studied. Collimated beam instantaneous thermal blooming phase compensation is simulated by using the laser atmospheric propagation four-dimension (4-D) code which is independently developed. The effect of deformable mirror (DM) actuators layout on the phase compensation efficiency under different thermal blooming strength is numerically analyzed. The results show that the layout of DM actuators has great effect on the AO system close-loop control stability. When the layout of DM actuators is different, the variance of DM actuators commands is also different. The proper layout of DM actuator can improve the AO system close-loop control stability, increase the threshold value of phase compensation instability (PCI).

The effect of atmospheric refraction on target positioning of electro-optical system is investigated. The formula is deduced to calculate the actual position and the probe position of the target. The simulation based on US Standard Atmosphere 1976 was carried out, the error of target positioning in different range and different angle was calculated, and the offset value was given, which can be used for compensating the target positioning.

Based on atmospheric particles and conventional meteorological data from Feb.8 to Feb.19 of 2013 in Hefei, according to the discharge of fireworks, type of precipitation, relative humidity and wind speed characteristics, the variation characteristics of PM2.5 mass concentration in different meteorological conditions were analyzed. The results showed that: during the Spring Festival in Hefei the average value of PM2.5 mass concentration was 58.3 μg/m3, PM2.5 mass concentration pollution occured only two days. PM2.5 mass concentration, caused by urban residents concentrated fireworks discharge, increased rapidly, but the discharge are mostly ultrafine particles (PM1). PM2.5 mass concentration of precipitation with wet deposition effect, the greater the precipitation process is, the greater the amount of wet deposition of PM2.5 mass concentration will be. Different size scales particles have different hygroscopic growth characteristics, and the correlation coefficients of PM1, PM1～2.5 and PM2.5～10 and relative humidity were 0.45, 0.26 and －0.07. The smaller the size scale particles is, the more obvious the hygroscopic growth properties will be. Evolution of PM2.5 mass concentration was negatively correlated with wind speed, the correlation coefficient is －0.33. The greater the wind speed is, the greater the diffusion capacity of particulate matter will be.

A new technology of NO2 concentration measurement based on the non-dispersive optical method is studied. On the basis of intensive absorption of NO2 in the ultraviolet-visible waveband, and according to the Lambert-Beer’s law, the concentration of NO2 can be derived by the relation curve of gas absorption rate and concentration calibrated in advance. The spectrometer, xenon lamp and a series of standard sample gas were used in the laboratory experiment. Four wavebands of 5 nm bandwidth were abstracted from the spectral data of 290～410 nm from spectrometer measurement; the absorption rates of different concentrations were calculated, and the polynomial fitting with gas concentration was made. The fitting correlation coefficients in different wavebands and fitting orders were compared, the best waveband and fitting order were obtained, and the selection basis of filter was provided.

To understand the effect of polarization effect of the imperfect lens components and angle error of linear polarizers on polarimetric precision of the aerosol polarimeter, firstly, the polarization degree of lens component is deducted by combining the Jones matrix of lens component with the coherent matrix of incident beam. Secondly, the polarimetric error of the instrument is estimated by using Mueller matrix, considering all effects of the polarization states of incident beam, polarization effect of lens component and the azimuth errors of polarizers. Finally, the polarization degree of lens components and the polarimetric error of the instrument are specifically computed, respectively. At the channel of 0.67 μm, the maximum of polarization degree of the lens component and absolute polarimetric error of the instrument are 0.3143 and 0.2838, respectively. At the channel of 1.64 μm, the maximum of polarization degree of the lens component and absolute polarimetric error of the instrument are 0.3249 and 0.2937 respectively. It is indicated that the major error of the polarimeter arise from polarization effect of the imperfect lens components and a great error exists if the instrument is not calibrated.

The reflectivity, polarization degree, intensity contrast and polarization contrast of s light and p light which scattered from aluminous plane and concrete floor, were theoretically calculated based on the specular reflected model at visible and near infrared under natural illumination condition. The results of calculation and analysis indicated that the polarization characteristics of object were determined by the difference of reflected capabilities of s light and p light. Then the difference was influenced by incident angle, wavelength, the surface roughness of object and the refractive index of the material. And the intensity contrast and polarization contrast were influenced by them firsthand. Consequently, the research of surface characteristics of object and background are of great significance for object detection and recognition in the mix natural background.

The transient responses of the CALIOP instrument in the 532 nm parallel and perpendicular channel are derived and analyzed from the CALIOP level 1 version 3 products in the winter and summer of 2008. The results show that there is great difference between winter and summer in northern hemisphere. For the reason that Antarctic and Greenland are almost entirely covered by snow and ice all the year round, the characteristic of transient response on these land cloud be a basis for judging whether the transient response is caused by snow or ice in somewhere else. The distribution statistics of about 41.8% samples in winter are the same as that of the samples in summer in northern hemisphere. It means these areas are not covered by snow and ice. The other 52.8% samples’ statistics are consistent with the samples on Antarctic and Greenland, indicating that these areas are covered by snow and ice.

In order to adapt the portable DTF-6 sun-photometer to the wild harsh environment, and to achieve outdoor long-term automatic unmanned measurements, development of automatic protection system for DTF-6 sun photometer is necessary. From the system’s overall control scheme, mechanical design, microcontroller automatic control system design, PC software design are introduced here. In the automatic protection mode, DTF-6 sun-tracking movements and the water-resistant automatic control system are simulated more than once. The results of experiments show that the system can achieve 24-hour sun-photometer automatic measurement and protection, which has a certain rationality and reliability.

Micro-thermometer is an important tool to measure the refractive index structure constant. The rapid change of atmospheric temperature is the measuring object, so accurate and effective signal collection of temperature fluctuation is the precondition of demarcating micro-thermometer successfully. In view of two-channel wind tunnel micro-thermometer calibrating system, the multiple-channel data acquisition program is programed based on PCI-1002 acquisition card. With the combination of high-precision timer of Windows operation system and MFC programming frame, the accurate and efficient multiple-channel acquisition to temperature fluctuation signal is performed, and the data sets are displayed, stored and computed in computer systems at the same time. The results show that by using high-precision timer of Windows system, the data gathering program works properly and can provide a reliable support for micro-thermometer experiment.

As the core element of a 532 nm Doppler lidar, Fabry-Perot etalon has direct effects on the velocity sensitivity and measurement precision. The reason of selecting 532 nm as the laser wavelength was analyzed by simulating the received signal. Optimizations of the free spectral range, full width at half maximum and peak value interval in three channels were presented by analyzing the velocity sensitivity and relative error. 9 GHz is selected as the free spectral range, and 1.75 GHz as the full width at half maximum, 4 GHz and 1.125 GHz as the interval between two edge channels and between the edge channel and locking channel respectively. The precision during processing and parallelism adjusting during experiment of the etalon was analyzed by simulating effects on the transmission of the main defects. 5 nm of processing precision and 10 nm of the maximal difference of the etalon spacing are required in the system.

In an effort to extend the stroke of micro-actuators in micro-deformable mirrors, out-of-plane actuators with curved electrode and clamped-clamped beam are investigated. The static behaviors of actuators are solved by using the Rayleigh-Ritz method. During the calculation, tension stress and residual stress were considered. By studying the effects in stroke of actuators with different electrode shapes, actuators with a 500 μm long beam with a maximum stroke of 14.1 μm are obtained when subjected to the voltage of 300 V.